Arteriosclerosis, generally known for thickening and hardening of the arterial wall, is responsible for the majority of deaths in the United States and most westernized countries. Atherosclerosis, one type of arteriosclerosis, is the cause for disorder of the larger arteries that underlies most coronary artery disease, aortic aneurysm, arterial disease of the lower extremities, and cerebrovascular disease. Atherosclerosis is characterized by an accumulation of lipid-filled smooth muscle cells, macrophages, and fibrous tissues, commonly known as atheroma or plaque, in focal areas of cardiovascular tissues, especially the aorta.
Numerous approaches for treating the diseased aorta have been proposed, including balloon angioplasty, laser angioplasty, and atherectomy. Removal of the atheroma is generally performed percutaneously through insertion of medical devices, e.g., a catheter and/or imaging probe, through a peripheral artery, such as the femoral artery. The devices are then advanced to the region of interest through the aorta.
Unfortunately, there are several disadvantages associated with these approaches. First, inserting and manipulating devices through the aorta may cause significant aortic trauma, resulting in aortic dissection, aortic wall hematoma, and/or embolization of calcium plaque from the aortic wall. Embolization of aortic plaque is a common cause of cerebral infarction or ischemia. Second, patients who have significant aortic atherosclerosis often have diseased peripheral arteries. Insertion of medical devices through the stenotic femoral arteries is often difficult and risky, because distal embolization and occlusion of the lower extremities can arise as a result of manipulating the diseased femoral artery. Thirdly, mechanical manipulation of the aorta during cardiothoracic surgeries, either in open thoracotomy or minimally invasive procedures, is a common cause for dislodgment of plaque, causing embolic stroke. Excision of high-risk atheromatous plaque from the aorta or cardiac tissues prior to cardiothoracic surgeries is therefore desired. The percutaneous approach requires an additional incision on a peripheral artery and therefore involves additional risk of vascular trauma and embolization.
New devices and methods are therefore needed that provide direct access to a patient's cardiovascular tissue for removal of atheromatous plaque(s) prior to or during cardiovascular surgeries, and that minimize the risk of peripheral embolization.